We study the valuation of state-issued tax-exempt municipal bonds and find that there are significant convenience premia in their prices. These premia parallel those identified in Treasury markets. We find evidence that these premia are tax related. Specifically, the premia are related to measures of tax and fiscal uncertainty, forecast flows into state municipal bond funds, and are directly linked to outmigration from high-tax to low-tax states and to other measures of tax aversion such as IRA and retirement plan contributions. These results suggest that investors are willing to pay a substantial premium to avoid taxes.

We provide estimates of Treasury convenience premia across the entire term structure of Treasury bills, notes, and bonds over more than a quarter of a century and document a variety of key stylized facts about their time‐series and cross‐sectional patterns. These results raise concerns about the evolving nature of Treasury markets and suggest that investors may now place less weight on the traditional role of Treasury securities as liquid trading vehicles. These stylized facts provide empirical benchmarks that could help guide future theoretical and empirical work about the economics of safe assets in financial markets.

We show that the price of a Treasury bond and an inflation‐swapped Treasury Inflation‐Protected Securities (TIPS) issue exactly replicating the cash flows of the Treasury bond can differ by more than $20 per $100 notional. Treasury bonds are almost always overvalued relative to TIPS. Total TIPS‐Treasury mispricing has exceeded $56 billion, representing nearly 8% of the total amount of TIPS outstanding. We find direct evidence that the mispricing narrows as additional capital flows into the markets. This provides strong support for the slow‐moving‐capital explanation of arbitrage persistence.